The long term goal of the proposed research is to develop a non-invasive system for screening and/or monitoring for preclinical arteriosclerosis. The achievement of this goal is envisioned as occurring in three concurrent phases: 1) improvement and testing the transducer for monitoring arterial pulse contours; 2) accumulation of records from patients with known cardiovascular disease; and 3) analysis of pulse tracings in terms of mathematical models of the circulation. We have developed a novel miniaturized pressure transducer that permits the measurement of pulse pressures on the surface of the skin over a frequency range of DC to approximately 10KHz. This system has proven to be extremely accurate in animal studies, yet is of such a size and potential cost that multichannel and hence multi-position recording of the pulse profile is feasible. Preliminary studies in patients have also shown that the transducer can provide accurate high frequency records of the radial, brachial, and carotid pulse traces. Future non-invasive transducers will be made to provide traces from less accessible pulses such as the popliteal, axillary, dorsalis pedis, and femoral pulses in obese patients. Records from outpatients with known diagnoses will be obtained in the Cardiology Clinic of the University of Chicago. Three broad categories of disease will be studied: 1) those which change pump output (aortic stenosis, aortic insufficiency, cardiac failure, ventricular aneurysm); 2) those which change compliance of large vessels (generalized atherosclerosis, single placques, coarctation); and 3) those which affect the capillary run-off (microvascular disease as seen in diabetes and hypertension). Meaningful interpretations of contours will be achieved by mathematically analyzing the wave propagation in peripheral systems. The analysis techniques have already been developed by the investigators and previously used to study the central arterial systems. If the above studies prove successful, we plan to modify the instrumentation so that it can be used by paramedical personnel in a population screening mode.